Background: Guillain-Barré syndrome (GBS) is an acute polyradiculoneuropathy, thought to be an autoimmune process. Although cases of GBS have been reported following a wide range of vaccines, a clear association has only been established with the 1976 H1N1 inactivated influenza vaccine.
Methods: We identified hospitalized GBS cases from Kaiser Permanente Northern California (KPNC) from 1995 through 2006. The medical record of each suspected case was neurologist-reviewed according to the Brighton Collaboration GBS case definition; only confirmed cases were included in the analyses, and cases of Miller Fisher syndrome were excluded. Using a case-centered design, we compared the odds of vaccination in the 6 and 10 weeks prior to onset of GBS to the odds of vaccination during the same time intervals in all vaccinated individuals in the entire KPNC population.
Results: We confirmed 415 incident cases of GBS (including Brighton levels 1, 2, and 3) during the study period (>30 million person-years). Incidence peaked during the winter months. The odds ratio of influenza vaccination within a 6-week interval prior to GBS, compared with the prior 9 months, was 1.1 (95% confidence interval [CI], .4-3.1). The risk in the 6-week interval compared to the prior 12 months for tetanus diphtheria combination, 23-valent pneumococcal polysaccharide, and for all vaccines combined was 1.4 (95% CI, .3-4.5), 0.7 (95% CI, .1-2.9), and 1.3 (95% CI, .8-2.3), respectively.
Conclusions: In this large retrospective study, we did not find evidence of an increased risk of GBS following vaccinations of any kind, including influenza vaccination.
Keywords: Guillaine-Barré syndrome; immunizations; influenza; safety; vaccine.